7. as you read this paragraph from an article about global warming, look for clues about the author's point of view:
corals, the small sea creatures that form the spectacular coral reefs, are also endangered by global warming. as the ocean temperatures rise,
the balance between corals and algae in the reefs is thrown off, and the corals die. additionally, the oceans are becoming more acidic as they
take in excess carbon dioxide from the air. corals do not grow well in water with a high acid content. in the last twenty years, corals have been
affected by global warming in all parts of the world. and since corals are a main food source for many sea animals, less coral could mean trouble
for other marine life, including fish that humans eat.

what level of knowledge about corals does this author seem to have?

a. a tour guide's knowledge

b. a fishing boat captain's knowledge

c. a politician's knowledge

d. a marine biologist's knowledge